<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <link rel="stylesheet" href="./css/index.css" />
    <title>记事本</title>
  </head>
  <body>
    <!-- 主体区域 -->
    <section id="app">
      <!-- 输入框 -->
      <header class="header">
        <h1>小黑记事本</h1>
        <input placeholder="请输入任务" class="new-todo" v-model="title" />
        <button class="add" @click="add()">添加任务</button>
      </header>
      <!-- 列表区域 -->
      <section class="main">
        <ul class="todo-list">
          <li v-for="(item , index) in list" :key="item.id" class="todo">
            <div class="view">
              <span class="index">{{index+1}}</span>
              <label>{{item.title}}</label>
              <button class="destroy" @click="del(index)"></button>
            </div>
          </li>
        </ul>
      </section>
      <!-- 统计和清空 -->
      <footer class="footer">
        <!-- 统计 -->
        <span class="todo-count">合 计:<strong> {{list.length}} </strong></span>
        <!-- 清空 -->
        <button class="clear-completed" @click="clear()">清空任务</button>
      </footer>
    </section>

    <!-- 底部 -->
    <script src="https://cdn.jsdelivr.net/npm/vue/dist/vue.js"></script>
    <script>
      let num = 0;
      const app = new Vue({
        el: "#app",
        data: {
          title: "",
          list: [
            { id: 1, title: "吃饭饭" },
            { id: 2, title: "睡觉觉" },
            { id: 3, title: "喝水水" },
          ],
        },
        methods: {
          add() {
            this.list.push({ id: Date.now(), title: this.title });
            this.title = "";
          },
          del(index) {
            this.list.splice(index, 1);
          },
          clear() {
            this.list = [];
          },
        },
      });
    </script>
  </body>
</html>
